title: Hydrogen sulfide alleviates hypoxia-induced root tip death in Pisum sativum.
abstract: Flooding of soils often results in hypoxic conditions surrounding plant roots, which is a harmful abiotic stress to crops. Hydrogen sulfide (H2S) is a highly diffusible, gaseous molecule that modulates cell signaling and is involved in hypoxia signaling in animal cells. However, there have been no previous studies of H2S in plant cells in response to hypoxia. The effects of H2S on hypoxia-induced root tip death were studied in pea (Pisum sativum) via analysis of endogenous H2S and reactive oxygen species (ROS) levels. The activities of key enzymes involved in antioxidative and H2S metabolic pathways were determined using spectrophotometric assays. Ethylene was measured by gas chromatography. We found that exogenous H2S pretreatment dramatically alleviated hypoxia-induced root tip death by protecting root tip cell membranes from ROS damage induced by hypoxia and by stimulating a quiescence strategy through inhibiting ethylene production. Conversely, root tip death induced by hypoxia was strongly enhanced by inhibition of the key enzymes responsible for endogenous H2S biosynthesis. Our results demonstrated that exogenous H2S pretreatment significantly alleviates hypoxia-induced root tip death in pea seedlings and, therefore, enhances the tolerance of the plant to hypoxic stress.
authors.affiliation: MOE Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, PR China.
authors.forename: Wei
authors.initials: W
authors.lastname: Cheng
authors.forename: Liang
authors.initials: L
authors.lastname: Zhang
authors.forename: Chengjin
authors.initials: C
authors.lastname: Jiao
authors.forename: Miao
authors.initials: M
authors.lastname: Su
authors.forename: Tao
authors.initials: T
authors.lastname: Yang
authors.forename: Lina
authors.initials: L
authors.lastname: Zhou
authors.forename: Renyi
authors.initials: R
authors.lastname: Peng
authors.forename: Ranran
authors.initials: R
authors.lastname: Wang
authors.forename: Chongying
authors.initials: C
authors.lastname: Wang
mesh_terms: D000222:Adaptation, Physiological; D015687:Cell Hypoxia; D002462:Cell Membrane; D005030:Ethylenes / Q000378:metabolism; D055868:Floods; D006862:Hydrogen Sulfide / Q000378:metabolism* / Q000494:pharmacology; D053858:Metabolic Networks and Pathways; D018384:Oxidative Stress; D010100:Oxygen / Q000378:metabolism*; D018532:Pisum sativum / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism*; D059828:Plant Cells / Q000378:metabolism; D018517:Plant Roots / Q000187:drug effects / Q000378:metabolism*; D017382:Reactive Oxygen Species / Q000378:metabolism; D036226:Seedlings; D014867:Water
chemical_list: D005030:Ethylenes; D017382:Reactive Oxygen Species; D014867:Water; C036216:ethylene; D010100:Oxygen; D006862:Hydrogen Sulfide
keywords: Abiotic stress; Ethylene; H(2)S; Hypoxic stress; Pea; ROS